The invention relates to means for spacing the plates of a viscous coupling which as outer plates are provided with outer teeth and non-rotatingly engage corresponding inner teeth of a coupling housing and which as inner plates are provided with inner teeth and non-rotatingly engage corresponding outer teeth of an inner plate carrier. The spacing means holding the associated plates at a predetermined distance from one another.
Such viscous couplings, as they are known from DE 38 28 421 C1, for example, are used for instance in the drive assembly of a four wheel drive vehicle. The coupling housing is usually provided with inner teeth in which the outer plates are arranged so as to be non-rotating, with spacing rings formed of wire which is bent so as to be circular holding the outer plates at a distance from one another so that they are axially immovable. The inner teeth in the inner wall of the coupling housing are usually produced by broaching. The disadvantage of this design is that dead spaces occur between the individual outer plates in the inner teeth, radially outside the spacing rings. These dead spaces may cause problems when filling the interior of the coupling housing with a viscous medium.
Furthermore, such spacing rings cannot be fitted by automatic means because they have to be pretensioned in order to rest securely against the inner wall of the housing and not reach the operational range of the inner plates.